Abstract: GaAs IR window slabs having largest dimensions that are greater than 8 inches, and preferably greater than 12 inches, are grown using the Horizontal Gradient Freeze (HGF) method. Heat extraction is simplified by using a shallow horizontal boat that is only slightly deeper than the desired window thickness, thereby enabling growth of large slabs while also minimizing material waste and fabrication cost as compared to slicing and shaping thick plates from large, melt-grown boules. Single crystal seeds can be used to optimize the final orientation of the slabs and minimize secondary nucleation, thereby maximizing yield. A conductive doped GaAs layer can be applied to the IR window slab to provide EMI shielding. The temperature gradient during HGF can be between 1° C./cm and 3° C./cm, and the directional solidification can be at a rate of between 0.25 mm/h and 2.5 mm/h.

Abstract: A method of manufacturing a structurally competent, EMI-shielded IR window includes using a mathematical model that combines the Sotoodeh and Nag models to determine an optimal thickness and dopant concentration of a doped layer of GaAs or GaP. A slab of GaAs or GaP is prepared, and a doped layer of the same material having the optimal thickness and dopant concentration is applied thereto. In embodiments, the doped layer is applied by an HVPE method such as LP-HVPE, which can also provide enhanced GaAs transparency near 1 micron. The Drude model can be applied to assist in selecting an anti-reflective coating. If the model predicts that the requirements of an application cannot be met by a doped layer alone, a doped layer can be applied that exceeds the required IR transparency, and a metallic grid can be applied to improve the EMI shielding, thereby satisfying the requirements.

Abstract: A method, system, and computer readable medium for performing a scalar agile parameter estimation for continuous-valued univariate parameters to estimate and track a likelihood of a measurement where a parameter distribution domain of an emitter is unknown, comprising: receiving a signal from an emitter source; measuring a feature of said signal; calculating a likelihood of said feature by a feature likelihood tracking model; adding a new parameter source model by creating a node, based on said feature likelihood; establishing a likelihood of a measurement using a measurement likelihood tracking model; starting a new feature track, based on said measurement likelihood; and assigning said feature to a track.

Abstract: IR window slabs of GaP greater than 4 inches diameter, and of GaAs greater than 8 inches diameter, are grown on a substrate using Hydride Vapor Phase Epitaxy (HVPE), preferably low pressure HVPE (LP-HVPE). Growth rates can be hundreds of microns per hour, comparable to vertical melt growth. GaAs IR windows produced by the disclosed method exhibit lower absorption than crystals grown from vertical melt near 1 micron, due to reduced impurities and reduced growth temperatures that limit the solubility of excess arsenic, and thereby reduce the “EL2” defects that cause high absorption near one micron in conventional GaAs boules. Silicon wafers can be used as HVPE substrates. For GaAs, layers of GaAsP that vary from 0% to 100% As can be applied to the substrate. EMI shielding can be applied by adding a dopant during the final stage of growth to provide a conductive GaAs or GaP layer.

Abstract: A method of making GaP window slabs having largest dimensions of greater than 4 inches and GaAs IR window slabs having largest dimensions of greater than 8 inches, includes slicing and dicing at least one smaller GaAs or GaP single crystal boule, which can be a commercial boule, to form a plurality of rectangular slabs. The slabs are ground to have precisely perpendicular edges, which are polished to be ultra-flat and ultra-smooth, for example to a flatness of at least ?/10, and a roughness Ra of less than 10 nanometers. The slab edges are then aligned and fused via optical-contacting/bonding to create a large GaAs or GaP slab having negligible bond interface losses. A conductive, doped GaAs or GaP layer can be applied to the window for EMI shielding in a subsequent vacuum deposition step, followed by applying anti-reflection (AR) coatings to one or both of the slab faces.

Abstract: A method of growing large GaAs or GaP IR window slabs by HVPE, and in embodiments by LP-HVPE, includes obtaining a plurality of thin, single crystal, epitaxial-quality GaAs or GaP wafers, cleaving the wafers into tiles having ultra-flat, atomically smooth, substantially perpendicular edges, and then butting the tiles together to form an HVPE substrate larger than 4 inches for GaP, and larger than 8 inches or even 12 inches for GaAs. Subsequent HVPE growth causes the individual tiles to fuse by optical bonding into a large “tiled” single crystal wafer, while any defects nucleated at the tile boundaries are healed, causing the tiles to merge with themselves and with the slab with no physical boundaries, and no degradation in optical quality. A dopant such as Si can be added to the epitaxial gases during the final HVPE growth stage to produce EMI shielded GaAs windows.

Abstract: Techniques are provided for automatic gain control. A methodology implementing the techniques according to an embodiment includes imparting, by a first adjustable attenuator, a first attenuation to a received radio frequency signal to generate a first attenuated signal. The first attenuation is based on a first control signal. The method also includes imparting, by a second adjustable attenuator, a second attenuation to the first attenuated signal to generate a second attenuated signal. The second attenuation is based on a second control signal. The method further includes converting, by an analog-to-digital converter, the second attenuated signal to a digital signal and measuring, by a processor based system, the ratio of peak power of the digital signal to average power of the digital signal, to generate a peak-to-average ratio (PAR) value. The first control signal and the second control signal are generated based in part on the PAR value.

Abstract: Techniques are provided for jammer detection. A methodology implementing the techniques according to an embodiment includes estimating an angle of arrival of a jamming signal, the jamming signal included in a received signal, and generating a direction finding (DF) confidence indicator associated with the estimated angle of arrival. The method also includes extracting the jamming signal from the received signal. The method further includes correlating the extracted jamming signal with previously extracted jamming signals to generate a correlation score and using the correlation score as a uniqueness assessment of the extracted jamming signal. The method further includes identifying characteristics of the extracted jamming signal and generating a characterization confidence indicator. The method further includes demoting the extracted jamming signal to non-jammer status based on one or more of the DF confidence indicator, the uniqueness assessment, and the characterization confidence indicator.

Abstract: A laser canard test system (LCTS) that includes a test bench assembly, at least one laser controller operably engaged with the test bench assembly, at least one laser sensor device operably engaged with the test bench assembly and in electrical communication with the at least one laser controller, and a canard testing protocol in logical communication with the at least one laser controller and the at least one laser sensor device to enable the at least one laser controller to command the at least one laser device to measure at least one canard on a payload free from contacting the at least one canard of the payload.

Abstract: An antenna calibration system and method utilizes both computer electromagnetic modeling and actual test fixture measurements for calibrating the antenna or multiple antennas in an array. Use of the test fixture measurements enables the calibration technique to account for design nuances or imperfections in each respective antenna to enable that particular antenna to be more accurately modeled for calibration without having to physically maneuver the platform to calibrate the antenna that is to be installed thereon. Use of computer electromagnetic modeling techniques then account for these design nuances or imperfections to provide improved modeling for calibrating the antenna on a platform prior to moving the platform with the antennas on the platform.

Abstract: An isolation assembly for use with a munition includes a housing extending along a central axis and defining a cavity. A shuttle is at least partially within the cavity with an air gap between the shuttle and the housing, where the shuttle is configured to contain one or more electronic components. An isolation assembly in the gap between the shuttle and the housing includes an elastomeric isolator and one or more seals. The isolation assembly retains the shuttle in the cavity with six degrees of freedom.

Abstract: An active infrared system may include at least one metamaterial optical element. The active infrared system may also include at least one lens assembly optically aligned with the at least one metamaterial optical element. The active infrared system may also include at least one active camera optically aligned with the at least one metamaterial optical element. The at least one metamaterial optical element of the active infrared system may also be configured with at least a reflection mode for reflecting at least one light waveband reflected by a remote object and a transmission mode for transmitting a uniform background light that is wider than the at least one light waveband reflected by the remote object.

Abstract: Flash peripheral device may include a kernel in logical communication with a bootloader where the kernel, when initialized, is adapted to upload in at least one hardware controller via the bootloader. Flash peripheral device may also include at least one firmware protocol in logical communication with the kernel and configured to initialize at least one hardware driver of the at least one hardware controller. Flash peripheral device may also include an operation application in logical communication with the kernel and provided with a legacy set of instructions and at least one updated set of instructions. The operation application executes and runs the at least one updated set of instructions when the at least one updated set of instructions is flashed to the operation application or executes and runs the legacy set of instructions when the at least one updated set of instructions fails to be flashed to the operation application.

Abstract: An apparatus for dampening at least one optical instrument on a military platform. The apparatus includes a plate adapted to hold at least one optical instrument. The apparatus also includes at least one dampening assembly having a first end operably engaged with the plate and an opposing second end operably engaged with a platform. The at least one dampening assembly is also adapted to reduce the movement of the plate and optical device from a ballistic event created by a ballistic device on the platform.

Abstract: A feature detection system, the system comprising: at least one processor in operative communication with a signal source, said processor further comprising at least one non-transitory storage medium, wherein at least one non-transitory storage medium contains instructions configured to cause the processor to: apply a joint group sparse denoising and delay estimation approach to a signal received from said signal source; and output statistics regarding the signal, wherein the joint group sparse denoising and delay estimation approach comprises; using the following equation: { x * , ? * } = argmin x , ? ? { 1 2 ? ? j = 1 M ? y j - x ? 2 2 + ? i = 0 N ? i ? ? i ( D i l i ? x ) } where: ?i are regularization functions; ?y?x?22 is a data-fidelity term and, in embodiments, is chosen as the least-square term; li are real numbers; Di are operators, which may be linear filters that can be written in matrix form; ?i are regularization parameters; and x*

Abstract: A transceiver having a down-converter for converting a radio-frequency (RF) input signal to an intermediate frequency (IF) signal with an analog low latency bypass path coupled to the IF signal and configured to provide a low latency IF signal and an up-converter for converting an IF signal to an RF signal. There is a digital path coupled to the IF signal and configured to provide a digitally processed IF signal, and an up-converter for converting at least one of the low latency IF signal and the digitally processed IF signal to an RF output signal. In a further example, the down-converter and the up-converter convert to millimeter wave frequencies and filters the millimeter wave frequencies with cavity filters.

Abstract: Techniques are disclosed for transmitting a secure message over a public or untrusted network. The techniques include receiving a message and creating multiple hash values of the message. A sending device signs and encrypts the message and hash values, then encapsulates and transmits to the message and hash values a security server. The security server receives and de-encapsulates the message and hash values, decrypts the message and hash values, and verifies the signature. The security server verifies the hash values and determines whether any changes were made to the message during transmission. If verified, the security server processes the message for transmission to the recipient. The security server creates multiple hash values of the original message, signs and encrypts the message and the hash values, encapsulates the message and hash values and transmits to a recipient device for further verification and presentation to the recipient.

Abstract: A method, system, and computer readable medium for performing a generalized angle-based tracker for a target determines angle-based information from a target signal, and initializes a Stationary Surface Filter (SSF), a Moving Surface Filter (MSF), and a Pseudorange Kalman Filter (PKF) with the angle-based information. Next, the SSF and MSF are scored by the PKF. If the information is associated, then the SSF, MSF, and PKF are updated. It is determined if at least one plausible Constituent Kalman Filter (CKF) exists for the SSF and MSF. If at least one CKF exists for the SSF and no CKF exists for the MSF, then the target is stationary surface; if at least one CKF exists for the MSF and no CKF exists for the SSF, then the target is moving surface; if no CKF exists for both the SSF and the MSF, then the target is moving airborne.

Abstract: Techniques are provided for batch processing signal acquisition. A batch processing signal acquisition system implementing the techniques according to an embodiment includes a recording controller configured to store samples of an input signal to a memory. The input signal is received at a first sampling rate. The system also includes a playback controller configured to read samples from the memory for playback of the input signal at a second sampling rate. The system further includes an acquisition processor configured to detect and locate, in time and frequency, a signal of interest in the playback of the input signal. The system further includes a signal processor configured to process the signal of interest in the playback of the input signal based on the detection and location provided by the acquisition processor.

Abstract: A transducer system comprising a housing, an electromechanical transducer within the housing, a wicking material adjacent to a portion of the electromechanical transducer, and a multi-phase coolant solution within the housing. The multi-phase coolant solution transitions from a first phase to a second phase in response to a temperature of the electromechanical transducer exceeding a threshold temperature. In some example cases, the multi-phase coolant solution has a boiling point of less than about 60° C., which effectively defines the threshold temperature. The multi-phase coolant solution may be chosen such that it remains a liquid during a first phase (cooling via conduction), and then evaporates during a second phase (cooling via conduction and convection) as the electromechanical transducer heats up.